cover
Article Per Year (5 Year)
All
Home Page
OAI Link
Editorial Team
Contact
Reviewer
Google Scholar
Contact Name
Risa Suryana
Contact Email
rsuryana@uns.ac.id
Phone
-
Journal Mail Official
ijap@uns.ac.id
Editorial Address
-
Location
Kota surakarta,
Jawa tengah
INDONESIA
INDONESIAN JOURNAL OF APPLIED PHYSICS
Published by Universitas Sebelas Maret
ISSN : 20890133     EISSN : 24776416     DOI : -
Core Subject : Science,
Astronomy Energy Materials Science & Nanotechnology Physics
Indonesia Journal of Apllied Physics provides rapid publication of short reports and important research in all fields of physics. Indonesia Journal of Apllied Physics publishes articles that are of significance in their respective fields whilst also contributing to the disclipline of physics as a whole. Articles should be submitted to the Editorial Office of Indonesia Journal of Apllied Physics through this site. Further information on submission is also available at this site
Arjuna Subject : -
Articles 351 Documents
 30   31   32   33   34 
Electrical Resistivity and Magnetoresistance Properties of Cation A-site substitution in La0.8-xAgxCa0.2MnO3 (x = 0.1 and 0.15) Dicky Rezky Munazat; Budhy Kurniawan; Rina Kamila; Maykel Manawan; Agung Imaduddin
INDONESIAN JOURNAL OF APPLIED PHYSICS Vol 15, No 2 (2025): October
Publisher : Department of Physics, Sebelas Maret University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.13057/ijap.v15i2.80160

Abstract

The polycrystalline sample of La0.8-xAgxCa0.2MnO3 (x = 0.1 and 0.15) has been successfully synthesized using a sol-gel method in our previous work. Here, we have investigated the electrical resistivity and magnetoresistance of both samples. All samples exhibited metallic behavior, as evidenced by the resistivity data measured in the temperature range from 9 to 285 K. As silver concentration increases, the resistivity decreases throughout the whole explored temperature range. Increasing silver ion concentration improves double exchange interaction (DE) between Mn3+ and Mn4+ which is responsible for gradually decreasing resistivity. The electrical transport is quite well described by a theory based on grain boundary factor, electron-electron interaction, and Kondo-like spin-dependent scattering mechanisms. Both samples show low-field magnetoresistance (LFMR) at low temperatures. The maximum magnetoresistance values for both samples were observed at 15 K, with values of -23.16% and -25.17% for x = 0.10 and 0.15, respectively.
Machine Learning-Based Cow Milk Quality Classification using Recursive Feature Elimination Cross-Validation Damar Wicaksono; Affix Mareta; Ardy Erdiyanto; Nuzula Afianah; Rafly Ramadhani
INDONESIAN JOURNAL OF APPLIED PHYSICS Vol 14, No 2 (2024): October
Publisher : Department of Physics, Sebelas Maret University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.13057/ijap.v14i2.85064

Abstract

Milk quality is of paramount importance as it directly impacts consumer health and well-being. High-quality milk is rich in essential nutrients such as calcium, protein, and vitamins, contributing to overall nutrition. Moreover, ensuring milk quality is vital for preventing the transmission of diseases and contaminants through dairy products. Therefore, research in this field is essential to guaranteeing the safety and nutritional value of milk consumed by individuals of all ages. In this paper, the design of machine learning-based grade measuring devices with recursive feature elimination with cross-validation (RFECV) is carried out as a guide in the design of a milk grade detection system. The milk is rated as low, medium, or high based on these criteria. The sensors will gather this information from the milk with the aid of the microcontroller. The algorithms utilized in this study and the results obtained from K-Nearest Neighbors (KNN) combined with the RFECV algorithm have a higher accuracy value: 17,20% better than the support vector machine (SVM) model, 25.37% better than the single K-Nearest Neighbors (KNN), and 26.37% better than the random forest (RF) model trained without RFECV. Using seven input features (pH, temperature, taste, odor, fat, turbidity, and color), the proposed model produces 96.27% accuracy.
Interpretation of 3 D Magnetic Inversion Results in the Majenang Area, Indonesia Accep Handyarso
INDONESIAN JOURNAL OF APPLIED PHYSICS Vol 15, No 1 (2025): April
Publisher : Department of Physics, Sebelas Maret University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.13057/ijap.v15i1.61501

Abstract

The Total Magnetic Intensity (TMI) data requires conversion using Reduction to Pole (RTP) or Reduction to Equator (RTE) filters prior to the interpretation process. However, the low latitude location causes stability issue in the RTP and is replaced by the RTE computing processes. Noteworthy, the RTE results have inverted polarity. An inverse modeling scheme based on direct use of TMI data using equivalent‑source provides an alternative solution to address this issue. In this research, synthetic modeling of a strike‑slip fault geometry is conducted to assist the interpretation process in order to guide during recognizing similar anomaly contour patterns in field datasets. TMI data interpretation was conducted in a volcanic area located in Majenang, Central Java. According to the research findings, a dextral strike‑slip fault with a northwest‑southeast lineament is delineated. This fault is interpreted as part of the Pamanukan‑Cilacap Fault Zone (PCFZ). Additionally, a circular anomaly is exposed and inferred to be the edge of ancient‑volcanic‑caldera (ring‑fault or caldera‑rims) in the study area. Both results were confirmed through a comparison of geomagnetic and gravity data. The high‑susceptibility zone correlates well with the high‑density zone and the outcrop of the Sangkur Volcano's intrusion body, which is inferred precedes the intrusion body of the Kumbang Volcano. The intrusive bodies located around the PCFZ manifest the presence of a weak zone that has been intruded by magmatism, contributing to the formation of volcanoes along the fault as a volcano‑tectonic setting in the area.
Magnetic behavior identification of high-purity hematite (Fe2O3) extracted from iron ore by co-precipitation method Fauzi Fauzi; Adi Rahwanto; Malahayati Malahayati; M. Nizar Machmud; Zulkarnain Jalil
INDONESIAN JOURNAL OF APPLIED PHYSICS Vol 15, No 2 (2025): October
Publisher : Department of Physics, Sebelas Maret University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.13057/ijap.v15i2.107933

Abstract

Magnetic mineral identification was successfully carried out on the iron ore from Manggamat in South Aceh Regency, Indonesia. This initial study was conducted in an attempt to increase the added value of local minerals. This study was performed by using co-precipitation method combined with mechanical milling and analyzed using X-ray diffraction and fluorescence (XRD, XRF) and the magnetic properties evaluated by Permagraph. These investigations indicate that the dominant phase in the Manggamat iron ore is hematite (Fe2O3), showed a content of 85.31%, followed by SiO2 compounds (11.01%), and the lowest concentration was SnO2 (0.02 %). Furthermore, observation of the magnetic properties showed that the magnetic saturation (Ms) of 0.1 Tesla, then residual magnetization or remanent (Br) of  0.017 Tesla, and a reverse magnetic field or coercivity (Hc) of 12.39 kA/m. As the milling time increased, the magnetic saturation and remanent field decreased, whereas the coercive field increased. This characteristic is known as the superparamagnetic behavior which widely used in biomedical application.
Estimation of Tsunami Hazard and Evacuation Sites using The Cornell Multigrid Couple Tsunami Method in South Button Regency Ilham Ilham; Jamhir Safani; Muliddin Muliddin; Teguh Sulistian; Sorja Koesuma
INDONESIAN JOURNAL OF APPLIED PHYSICS Vol 15, No 1 (2025): April
Publisher : Department of Physics, Sebelas Maret University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.13057/ijap.v15i1.97008

Abstract

The 1992 earthquake and tsunami in the Flores Sea proved that the tsunami impacted the people of the South Buton Region. This research aims to map tsunami hazards and estimate evacuation routes and sites in the South Buton Regency. These evacuation routes and sites are very crucial for disaster preparedness and reducing the risk of tsunami disasters. This research simulates the tsunami wave hazard from the 1992 Flores earthquake using the Cornell multigrid coupled tsunami (COMCOT). We designed the study area in five layers and seven sublayers, encompassing 13 villages on the coast of South Buton Regency. The research generated seven tsunami hazard maps based on the number of existing sublayers, each equipped with evacuation routes and locations. In general, the seven study areas have two tsunami hazard levels: a hazard level with an inundation height of less than 0.5 m and a hazard level with an inundation height of 0.5–3 m. The tsunami inundation distance for the height of 0.5-3 m varies. The shortest inundation distance is 5–33 m in Lakambau and Laompo Villages, while the farthest distance is 57–98 m in Katampe, Lamaninggara, and Molona Villages. Apart from that, the tsunami wave arrived around 35–45 minutes after the earthquake. The fastest arrival time is 35 minutes in Bahari Village, which is closest to the source of the tsunami. The results of the study recommend 17 temporary evacuation sites (TES) and 7 final evacuation sites (FES) in the research area.
Scanning Electron Microscopy and Magnetic Characterization of Iron Oxides in Suspended Sediments Sudarningsih Sudarningsih; Satria Bijaksana; Widodo Widodo; Irwan Iskandar; Darharta Dahrin; Silvia Jannatul Fajar; Kartika Hajar Kirana; Raghel Yunginger
INDONESIAN JOURNAL OF APPLIED PHYSICS Vol 14, No 2 (2024): October
Publisher : Department of Physics, Sebelas Maret University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.13057/ijap.v14i2.76582

Abstract

River sediment is the product of a sedimentation process in the river environment that originates from the weathering of bedrock or erosion processes, organic materials, particles, or anthropogenic substances. Previous research shows the magnetic mineral content in the sediments of the Citarum River and its tributaries. Suspended sediment was collected from the Citarum River and its tributaries in West Java, Indonesia, for mineralogical and granulometric analysis. The aim of this research is to distinguish between magnetic mineral sources, a scanning electron microscope equipped with energy dispersive X-ray spectroscopy (SEM-EDX), and rock magnetism. The hysteresis parameter verifies that the XRD measurement results show that the main magnetic minerals in suspended sediments are ferrimagnetic minerals such as magnetite (Fe3O4). According to the results of the SEM-EDX investigations, the magnetic granules in the Citarum River and its tributaries derive from two distinct sources: pedogenic and anthropogenic. The Citarum River and its tributaries’ magnetic granules are generally octahedral or angular in shape, with broken corners, indicating a pedogenic origin
Optimizing Formalin Detection in Fish Using QCM Sensors with TOMAC Membrane Coatings for Product Quality Monitoring Muthmainnah Muthmainnah; Khoirul Aini; Imam Tazi; Ninik Chamidah; Kusairi Kusairi
INDONESIAN JOURNAL OF APPLIED PHYSICS Vol 14, No 2 (2024): October
Publisher : Department of Physics, Sebelas Maret University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.13057/ijap.v14i2.92912

Abstract

Detection of formalin in fishery products is a significant concern in the food industry to ensure consumer safety. This study compared the performance of Quartz Crystal Microbalance (QCM) sensors without a membrane and with a Trioctyl methyl ammonium Chloride (TOMAC) membrane coating in detecting formalin in fish samples. The research findings indicate that QCM without a membrane for formalin samples has a lower detection limit of 150 ppm and an upper detection limit of 350 ppm with a sensitivity of 2194.171 Hz/ppm. On the other hand, QCM with a TOMAC membrane coating has a lower detection limit of 400 ppm and an upper detection limit of 550 ppm with a sensitivity of 842.7551 Hz/ppm. Meanwhile, QCM without a membrane for formalin in fish samples has a lower detection limit of 450 ppm and an upper detection limit of 650 ppm with a sensitivity of 15386.38 Hz/ppm. At the same time, QCM with a TOMAC membrane coating for formalin in fish samples has a lower detection limit of 350 ppm and an upper detection limit of 500 ppm with a sensitivity of 23108.9 Hz/ppm. Response time analysis shows that both sensors reach a steady state condition after 12 seconds. This study highlights the importance of selecting appropriate sensors for detecting formalin in fishery products, considering detection limits, sensitivity, and response time as crucial criteria. Thus, these findings can guide the fisheries industry in choosing effective and accurate formalin detection technology.
Implementation of CNN-SVM with Index Pattern-Based Feature Selection on PPG Signals for Cuffless Hypertension Detection Dafina Nazhifah; Wiharto Wiharto; Fajar Muslim
INDONESIAN JOURNAL OF APPLIED PHYSICS Vol 15, No 2 (2025): October
Publisher : Department of Physics, Sebelas Maret University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.13057/ijap.v15i2.102421

Abstract

Hypertension is one of the leading causes of death worldwide and often goes undetected due to its minimal symptoms. Early detection is crucial, and one non-invasive method involves the use of photoplethysmogram (PPG) signals. However, PPG signals contain a large number of features, which can lead to information redundancy and decreased model performance. This study proposes a hypertension detection system based on a CNN-SVM combination, preceded by feature selection using position-based indices (odd, even, specific multiples) to reduce data dimensionality and accelerate computation. The PPG signal dataset was obtained from 216 patients at UNS Hospital. After preprocessing and feature selection, feature extraction was performed using a Convolutional Neural Network (CNN), followed by classification using a Support Vector Machine (SVM). The model was evaluated under three classification scenarios: binary classification (normal vs. prehypertensive-hypertension and normal-prehypertension vs. hypertension) and three-class classification (normal, prehypertension, hypertension). The best classification accuracy achieved was 93.10% for the normal vs. prehypertension-hypertension scenario, 88.38% for normal-prehypertension vs. hypertension, and 82.79% for the three-class classification. This approach demonstrates that the combination of CNN-SVM with simple feature selection can improve both accuracy and efficiency in PPG-based hypertension detection.
Influence of Electrode Shape and Spacing on Corona Discharge Phenomena using a Plasma Generator Jefri Dharmesta; Salma Aulia Rohimah; Yudan Whulanza; Ario Sunar Baskoro
INDONESIAN JOURNAL OF APPLIED PHYSICS Vol 15, No 1 (2025): April
Publisher : Department of Physics, Sebelas Maret University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.13057/ijap.v15i1.90553

Abstract

Electrical discharges that happen near high-voltage conductors are known as corona discharges. It will produce light and sound as it ionises the surrounding air. The purpose of this work is to investigate how conductor form and spacing affect the properties of corona discharge produced by a plasma generator. In this study, conductor shapes such as triangle, W-shaped wire, syringe (point), and L-shaped wire (horizontal) were experimented with, as well as the distance between conductors. The outcome demonstrates that conductor spacing affects the corona discharge's plasma intensity, with shorter distances producing stronger electric fields and greater discharge intensities. Furthermore, the dispersion of the plasma is greatly influenced by the conductor's shape, since every conductor shape results in a different pattern of plasma distribution. These findings offer important new information for the development and improvement of systems that make use of corona discharge events.
Application of 1D Magnetotelluric Method to Estimate Alluvium Thickness in Aceh River Delta Fajrul Hani; Nazli Ismail; Muhammad Syukri Surbakti; Fadhli Syamsuddin; Amir Asyqari; Muhammad Nanda; Badrul Munir; Muhammad Arfan Alhafsi; Tomi Afrizal
INDONESIAN JOURNAL OF APPLIED PHYSICS Vol 16, No 1 (2026): April
Publisher : Department of Physics, Sebelas Maret University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.13057/ijap.v16i1.106868

Abstract

The Aceh River Delta, located in Banda Aceh City and Aceh Besar Regency, is a Quaternary alluvial plain composed of unconsolidated young sediments and lies between two northern branches of the Great Sumatran Fault, making it vulnerable to earthquake amplification and liquefaction. Estimating the thickness of alluvium is essential for seismic risk assessment. This study applies the 1D magnetotelluric (MT) method to investigate subsurface resistivity and estimate alluvium thickness. MT data were acquired in Cot Seunong Village using a KMS-820 data logger, LEMI-120 magnetometer, and LEMI-701 electrodes for 14 hours. Processing included time-frequency analysis, notch filtering, and robust transfer function estimation using the EMTF algorithm. Apparent resistivity and phase data were inverted using IPI2WIN to produce a 1D resistivity model. The model reveals seven subsurface layers to 1000 m depth, with the upper six layers (0–420 m) having low to moderate resistivity (13.9–134.9 Ωm), interpreted as alluvium. The deepest layer (914.2 Ωm) likely represents sandstone-conglomerate bedrock. The model correlates well with nearby borehole lithology. These findings confirm the effectiveness of the 1D MT method in estimating alluvium thickness and detecting resistivity contrasts. The estimated alluvium thickness of 420 m increases vulnerability to seismic wave amplification at the ground surface. Further surveys using 2D/3D MT inversion are recommended to provide comprehensive information on vertically and laterally subsurface conditions, thereby enhancing geohazard assessment in the Aceh River Delta.

Page 32 of 36 | Total Record : 351

 30   31   32   33   34 

Filter by Year

2013 2026


Reset
Filter By Issues
All Issue Vol 16, No 1 (2026): April Vol 15, No 2 (2025): October Vol 15, No 1 (2025): April Vol 14, No 2 (2024): October Vol 14, No 1 (2024): April Vol 13, No 2 (2023): October Vol 13, No 1 (2023): April Vol 12, No 2 (2022): October Vol 12, No 1 (2022): April Vol 11, No 2 (2021): October Vol 11, No 1 (2021): April Vol 10, No 01 (2020): April Vol 10, No 2 (2020): October Vol 9, No 02 (2019): October Vol 9, No 01 (2019): April Vol 8, No 2 (2018): October Vol 8, No 1 (2018): April Vol 6, No 02 (2016): October Vol 4, No 02 (2014): October Vol 7, No 2 (2017): October Vol 7, No 1 (2017): April Vol 6, No 01 (2016): April Vol 4, No 01 (2014): April Vol 3, No 02 (2013): October Vol 3, No 01 (2013): April Vol 2, No 02 (2012): October Vol 5, No 02 (2015): October Vol 5, No 01 (2015): April More Issue